Python 3.8.6rc1 (tags/v3.8.6rc1:08bd63d, Sep  7 2020, 23:10:23) [MSC v.1927 64 bit (AMD64)] on win32
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>>> "{} is {}".format("laoyou","teacher")
'laoyou is teacher'
>>> "{0} is {1}".format("laoyou","teacher")
'laoyou is teacher'
>>> "{1} is {0}".format("laoyou","teacher")
'teacher is laoyou'
>>> "{2} 在 {1} 跟着 {0} 学习".format("jinan","jinan univesity","laoyou")
'laoyou 在 jinan univesity 跟着 jinan 学习'
>>> "%s is %s"%("laoypu","teacher")
'laoypu is teacher'
>>> 